//     Underscore.js 1.8.2
//     http://underscorejs.org
//     (c) 2009-2015 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
//     Underscore may be freely distributed under the MIT license.
(function () {
    // Baseline setup
    // --------------
    // Establish the root object, `window` in the browser, or `exports` on the server.
    //   var root = this;
    //   // Save the previous value of the `_` variable.
    //   var previousUnderscore = root._;
    // Save bytes in the minified (but not gzipped) version:
    var ArrayProto = Array.prototype,
        ObjProto = Object.prototype,
        FuncProto = Function.prototype; // Create quick reference variables for speed access to core prototypes.

    var push = ArrayProto.push,
        slice = ArrayProto.slice,
        toString = ObjProto.toString,
        hasOwnProperty = ObjProto.hasOwnProperty; // All **ECMAScript 5** native function implementations that we hope to use
    // are declared here.

    var nativeIsArray = Array.isArray,
        nativeKeys = Object.keys,
        nativeBind = FuncProto.bind,
        nativeCreate = Object.create; // Naked function reference for surrogate-prototype-swapping.

    var Ctor = function () {}; // Create a safe reference to the Underscore object for use below.

    var _ = function (obj) {
        if (obj instanceof _) return obj;
        if (!(this instanceof _)) return new _(obj);
        this._wrapped = obj;
    }; // Export the Underscore object for **Node.js**, with
    // backwards-compatibility for the old `require()` API. If we're in
    // the browser, add `_` as a global object.
    //   if (typeof exports !== 'undefined') {
    //     if (typeof module !== 'undefined' && module.exports) {
    //       exports = module.exports = _;
    //     }
    //     exports._ = _;
    //   } else {
    //     root._ = _;
    //   }

    module.exports = _; // Current version.

    _.VERSION = '1.8.2'; // Internal function that returns an efficient (for current engines) version
    // of the passed-in callback, to be repeatedly applied in other Underscore
    // functions.

    var optimizeCb = function (func, context, argCount) {
        if (context === void 0) return func;

        switch (argCount == null ? 3 : argCount) {
            case 1:
                return function (value) {
                    return func.call(context, value);
                };

            case 2:
                return function (value, other) {
                    return func.call(context, value, other);
                };

            case 3:
                return function (value, index, collection) {
                    return func.call(context, value, index, collection);
                };

            case 4:
                return function (accumulator, value, index, collection) {
                    return func.call(context, accumulator, value, index, collection);
                };
        }

        return function () {
            return func.apply(context, arguments);
        };
    }; // A mostly-internal function to generate callbacks that can be applied
    // to each element in a collection, returning the desired result 鈥� either
    // identity, an arbitrary callback, a property matcher, or a property accessor.

    var cb = function (value, context, argCount) {
        if (value == null) return _.identity;
        if (_.isFunction(value)) return optimizeCb(value, context, argCount);
        if (_.isObject(value)) return _.matcher(value);
        return _.property(value);
    };

    _.iteratee = function (value, context) {
        return cb(value, context, Infinity);
    }; // An internal function for creating assigner functions.

    var createAssigner = function (keysFunc, undefinedOnly) {
        return function (obj) {
            var length = arguments.length;
            if (length < 2 || obj == null) return obj;

            for (var index = 1; index < length; index++) {
                var source = arguments[index],
                    keys = keysFunc(source),
                    l = keys.length;

                for (var i = 0; i < l; i++) {
                    var key = keys[i];
                    if (!undefinedOnly || obj[key] === void 0) obj[key] = source[key];
                }
            }

            return obj;
        };
    }; // An internal function for creating a new object that inherits from another.

    var baseCreate = function (prototype) {
        if (!_.isObject(prototype)) return {};
        if (nativeCreate) return nativeCreate(prototype);
        Ctor.prototype = prototype;
        var result = new Ctor();
        Ctor.prototype = null;
        return result;
    }; // Helper for collection methods to determine whether a collection
    // should be iterated as an array or as an object
    // Related: http://people.mozilla.org/~jorendorff/es6-draft.html#sec-tolength

    var MAX_ARRAY_INDEX = Math.pow(2, 53) - 1;

    var isArrayLike = function (collection) {
        var length = collection != null && collection.length;
        return typeof length == 'number' && length >= 0 && length <= MAX_ARRAY_INDEX;
    }; // Collection Functions
    // --------------------
    // The cornerstone, an `each` implementation, aka `forEach`.
    // Handles raw objects in addition to array-likes. Treats all
    // sparse array-likes as if they were dense.

    _.each = _.forEach = function (obj, iteratee, context) {
        iteratee = optimizeCb(iteratee, context);
        var i, length;

        if (isArrayLike(obj)) {
            for (i = 0, length = obj.length; i < length; i++) {
                iteratee(obj[i], i, obj);
            }
        } else {
            var keys = _.keys(obj);

            for (i = 0, length = keys.length; i < length; i++) {
                iteratee(obj[keys[i]], keys[i], obj);
            }
        }

        return obj;
    }; // Return the results of applying the iteratee to each element.

    _.map = _.collect = function (obj, iteratee, context) {
        iteratee = cb(iteratee, context);

        var keys = !isArrayLike(obj) && _.keys(obj),
            length = (keys || obj).length,
            results = Array(length);

        for (var index = 0; index < length; index++) {
            var currentKey = keys ? keys[index] : index;
            results[index] = iteratee(obj[currentKey], currentKey, obj);
        }

        return results;
    }; // Create a reducing function iterating left or right.

    function createReduce(dir) {
        // Optimized iterator function as using arguments.length
        // in the main function will deoptimize the, see #1991.
        function iterator(obj, iteratee, memo, keys, index, length) {
            for (; index >= 0 && index < length; index += dir) {
                var currentKey = keys ? keys[index] : index;
                memo = iteratee(memo, obj[currentKey], currentKey, obj);
            }

            return memo;
        }

        return function (obj, iteratee, memo, context) {
            iteratee = optimizeCb(iteratee, context, 4);

            var keys = !isArrayLike(obj) && _.keys(obj),
                length = (keys || obj).length,
                index = dir > 0 ? 0 : length - 1; // Determine the initial value if none is provided.

            if (arguments.length < 3) {
                memo = obj[keys ? keys[index] : index];
                index += dir;
            }

            return iterator(obj, iteratee, memo, keys, index, length);
        };
    } // **Reduce** builds up a single result from a list of values, aka `inject`,
    // or `foldl`.

    _.reduce = _.foldl = _.inject = createReduce(1); // The right-associative version of reduce, also known as `foldr`.

    _.reduceRight = _.foldr = createReduce(-1); // Return the first value which passes a truth test. Aliased as `detect`.

    _.find = _.detect = function (obj, predicate, context) {
        var key;

        if (isArrayLike(obj)) {
            key = _.findIndex(obj, predicate, context);
        } else {
            key = _.findKey(obj, predicate, context);
        }

        if (key !== void 0 && key !== -1) return obj[key];
    }; // Return all the elements that pass a truth test.
    // Aliased as `select`.

    _.filter = _.select = function (obj, predicate, context) {
        var results = [];
        predicate = cb(predicate, context);

        _.each(obj, function (value, index, list) {
            if (predicate(value, index, list)) results.push(value);
        });

        return results;
    }; // Return all the elements for which a truth test fails.

    _.reject = function (obj, predicate, context) {
        return _.filter(obj, _.negate(cb(predicate)), context);
    }; // Determine whether all of the elements match a truth test.
    // Aliased as `all`.

    _.every = _.all = function (obj, predicate, context) {
        predicate = cb(predicate, context);

        var keys = !isArrayLike(obj) && _.keys(obj),
            length = (keys || obj).length;

        for (var index = 0; index < length; index++) {
            var currentKey = keys ? keys[index] : index;
            if (!predicate(obj[currentKey], currentKey, obj)) return false;
        }

        return true;
    }; // Determine if at least one element in the object matches a truth test.
    // Aliased as `any`.

    _.some = _.any = function (obj, predicate, context) {
        predicate = cb(predicate, context);

        var keys = !isArrayLike(obj) && _.keys(obj),
            length = (keys || obj).length;

        for (var index = 0; index < length; index++) {
            var currentKey = keys ? keys[index] : index;
            if (predicate(obj[currentKey], currentKey, obj)) return true;
        }

        return false;
    }; // Determine if the array or object contains a given value (using `===`).
    // Aliased as `includes` and `include`.

    _.contains =
        _.includes =
        _.include =
            function (obj, target, fromIndex) {
                if (!isArrayLike(obj)) obj = _.values(obj);
                return _.indexOf(obj, target, typeof fromIndex == 'number' && fromIndex) >= 0;
            }; // Invoke a method (with arguments) on every item in a collection.

    _.invoke = function (obj, method) {
        var args = slice.call(arguments, 2);

        var isFunc = _.isFunction(method);

        return _.map(obj, function (value) {
            var func = isFunc ? method : value[method];
            return func == null ? func : func.apply(value, args);
        });
    }; // Convenience version of a common use case of `map`: fetching a property.

    _.pluck = function (obj, key) {
        return _.map(obj, _.property(key));
    }; // Convenience version of a common use case of `filter`: selecting only objects
    // containing specific `key:value` pairs.

    _.where = function (obj, attrs) {
        return _.filter(obj, _.matcher(attrs));
    }; // Convenience version of a common use case of `find`: getting the first object
    // containing specific `key:value` pairs.

    _.findWhere = function (obj, attrs) {
        return _.find(obj, _.matcher(attrs));
    }; // Return the maximum element (or element-based computation).

    _.max = function (obj, iteratee, context) {
        var result = -Infinity,
            lastComputed = -Infinity,
            value,
            computed;

        if (iteratee == null && obj != null) {
            obj = isArrayLike(obj) ? obj : _.values(obj);

            for (var i = 0, length = obj.length; i < length; i++) {
                value = obj[i];

                if (value > result) {
                    result = value;
                }
            }
        } else {
            iteratee = cb(iteratee, context);

            _.each(obj, function (value, index, list) {
                computed = iteratee(value, index, list);

                if (computed > lastComputed || (computed === -Infinity && result === -Infinity)) {
                    result = value;
                    lastComputed = computed;
                }
            });
        }

        return result;
    }; // Return the minimum element (or element-based computation).

    _.min = function (obj, iteratee, context) {
        var result = Infinity,
            lastComputed = Infinity,
            value,
            computed;

        if (iteratee == null && obj != null) {
            obj = isArrayLike(obj) ? obj : _.values(obj);

            for (var i = 0, length = obj.length; i < length; i++) {
                value = obj[i];

                if (value < result) {
                    result = value;
                }
            }
        } else {
            iteratee = cb(iteratee, context);

            _.each(obj, function (value, index, list) {
                computed = iteratee(value, index, list);

                if (computed < lastComputed || (computed === Infinity && result === Infinity)) {
                    result = value;
                    lastComputed = computed;
                }
            });
        }

        return result;
    }; // Shuffle a collection, using the modern version of the
    // [Fisher-Yates shuffle](http://en.wikipedia.org/wiki/Fisher鈥揧ates_shuffle).

    _.shuffle = function (obj) {
        var set = isArrayLike(obj) ? obj : _.values(obj);
        var length = set.length;
        var shuffled = Array(length);

        for (var index = 0, rand; index < length; index++) {
            rand = _.random(0, index);
            if (rand !== index) shuffled[index] = shuffled[rand];
            shuffled[rand] = set[index];
        }

        return shuffled;
    }; // Sample **n** random values from a collection.
    // If **n** is not specified, returns a single random element.
    // The internal `guard` argument allows it to work with `map`.

    _.sample = function (obj, n, guard) {
        if (n == null || guard) {
            if (!isArrayLike(obj)) obj = _.values(obj);
            return obj[_.random(obj.length - 1)];
        }

        return _.shuffle(obj).slice(0, Math.max(0, n));
    }; // Sort the object's values by a criterion produced by an iteratee.

    _.sortBy = function (obj, iteratee, context) {
        iteratee = cb(iteratee, context);
        return _.pluck(
            _.map(obj, function (value, index, list) {
                return {
                    value: value,
                    index: index,
                    criteria: iteratee(value, index, list)
                };
            }).sort(function (left, right) {
                var a = left.criteria;
                var b = right.criteria;

                if (a !== b) {
                    if (a > b || a === void 0) return 1;
                    if (a < b || b === void 0) return -1;
                }

                return left.index - right.index;
            }),
            'value'
        );
    }; // An internal function used for aggregate "group by" operations.

    var group = function (behavior) {
        return function (obj, iteratee, context) {
            var result = {};
            iteratee = cb(iteratee, context);

            _.each(obj, function (value, index) {
                var key = iteratee(value, index, obj);
                behavior(result, value, key);
            });

            return result;
        };
    }; // Groups the object's values by a criterion. Pass either a string attribute
    // to group by, or a function that returns the criterion.

    _.groupBy = group(function (result, value, key) {
        if (_.has(result, key)) result[key].push(value);
        else result[key] = [value];
    }); // Indexes the object's values by a criterion, similar to `groupBy`, but for
    // when you know that your index values will be unique.

    _.indexBy = group(function (result, value, key) {
        result[key] = value;
    }); // Counts instances of an object that group by a certain criterion. Pass
    // either a string attribute to count by, or a function that returns the
    // criterion.

    _.countBy = group(function (result, value, key) {
        if (_.has(result, key)) result[key]++;
        else result[key] = 1;
    }); // Safely create a real, live array from anything iterable.

    _.toArray = function (obj) {
        if (!obj) return [];
        if (_.isArray(obj)) return slice.call(obj);
        if (isArrayLike(obj)) return _.map(obj, _.identity);
        return _.values(obj);
    }; // Return the number of elements in an object.

    _.size = function (obj) {
        if (obj == null) return 0;
        return isArrayLike(obj) ? obj.length : _.keys(obj).length;
    }; // Split a collection into two arrays: one whose elements all satisfy the given
    // predicate, and one whose elements all do not satisfy the predicate.

    _.partition = function (obj, predicate, context) {
        predicate = cb(predicate, context);
        var pass = [],
            fail = [];

        _.each(obj, function (value, key, obj) {
            (predicate(value, key, obj) ? pass : fail).push(value);
        });

        return [pass, fail];
    }; // Array Functions
    // ---------------
    // Get the first element of an array. Passing **n** will return the first N
    // values in the array. Aliased as `head` and `take`. The **guard** check
    // allows it to work with `_.map`.

    _.first =
        _.head =
        _.take =
            function (array, n, guard) {
                if (array == null) return void 0;
                if (n == null || guard) return array[0];
                return _.initial(array, array.length - n);
            }; // Returns everything but the last entry of the array. Especially useful on
    // the arguments object. Passing **n** will return all the values in
    // the array, excluding the last N.

    _.initial = function (array, n, guard) {
        return slice.call(array, 0, Math.max(0, array.length - (n == null || guard ? 1 : n)));
    }; // Get the last element of an array. Passing **n** will return the last N
    // values in the array.

    _.last = function (array, n, guard) {
        if (array == null) return void 0;
        if (n == null || guard) return array[array.length - 1];
        return _.rest(array, Math.max(0, array.length - n));
    }; // Returns everything but the first entry of the array. Aliased as `tail` and `drop`.
    // Especially useful on the arguments object. Passing an **n** will return
    // the rest N values in the array.

    _.rest =
        _.tail =
        _.drop =
            function (array, n, guard) {
                return slice.call(array, n == null || guard ? 1 : n);
            }; // Trim out all falsy values from an array.

    _.compact = function (array) {
        return _.filter(array, _.identity);
    }; // Internal implementation of a recursive `flatten` function.

    var flatten = function (input, shallow, strict, startIndex) {
        var output = [],
            idx = 0;

        for (var i = startIndex || 0, length = input && input.length; i < length; i++) {
            var value = input[i];

            if (isArrayLike(value) && (_.isArray(value) || _.isArguments(value))) {
                //flatten current level of array or arguments object
                if (!shallow) value = flatten(value, shallow, strict);
                var j = 0,
                    len = value.length;
                output.length += len;

                while (j < len) {
                    output[idx++] = value[j++];
                }
            } else if (!strict) {
                output[idx++] = value;
            }
        }

        return output;
    }; // Flatten out an array, either recursively (by default), or just one level.

    _.flatten = function (array, shallow) {
        return flatten(array, shallow, false);
    }; // Return a version of the array that does not contain the specified value(s).

    _.without = function (array) {
        return _.difference(array, slice.call(arguments, 1));
    }; // Produce a duplicate-free version of the array. If the array has already
    // been sorted, you have the option of using a faster algorithm.
    // Aliased as `unique`.

    _.uniq = _.unique = function (array, isSorted, iteratee, context) {
        if (array == null) return [];

        if (!_.isBoolean(isSorted)) {
            context = iteratee;
            iteratee = isSorted;
            isSorted = false;
        }

        if (iteratee != null) iteratee = cb(iteratee, context);
        var result = [];
        var seen = [];

        for (var i = 0, length = array.length; i < length; i++) {
            var value = array[i],
                computed = iteratee ? iteratee(value, i, array) : value;

            if (isSorted) {
                if (!i || seen !== computed) result.push(value);
                seen = computed;
            } else if (iteratee) {
                if (!_.contains(seen, computed)) {
                    seen.push(computed);
                    result.push(value);
                }
            } else if (!_.contains(result, value)) {
                result.push(value);
            }
        }

        return result;
    }; // Produce an array that contains the union: each distinct element from all of
    // the passed-in arrays.

    _.union = function () {
        return _.uniq(flatten(arguments, true, true));
    }; // Produce an array that contains every item shared between all the
    // passed-in arrays.

    _.intersection = function (array) {
        if (array == null) return [];
        var result = [];
        var argsLength = arguments.length;

        for (var i = 0, length = array.length; i < length; i++) {
            var item = array[i];
            if (_.contains(result, item)) continue;

            for (var j = 1; j < argsLength; j++) {
                if (!_.contains(arguments[j], item)) break;
            }

            if (j === argsLength) result.push(item);
        }

        return result;
    }; // Take the difference between one array and a number of other arrays.
    // Only the elements present in just the first array will remain.

    _.difference = function (array) {
        var rest = flatten(arguments, true, true, 1);
        return _.filter(array, function (value) {
            return !_.contains(rest, value);
        });
    }; // Zip together multiple lists into a single array -- elements that share
    // an index go together.

    _.zip = function () {
        return _.unzip(arguments);
    }; // Complement of _.zip. Unzip accepts an array of arrays and groups
    // each array's elements on shared indices

    _.unzip = function (array) {
        var length = (array && _.max(array, 'length').length) || 0;
        var result = Array(length);

        for (var index = 0; index < length; index++) {
            result[index] = _.pluck(array, index);
        }

        return result;
    }; // Converts lists into objects. Pass either a single array of `[key, value]`
    // pairs, or two parallel arrays of the same length -- one of keys, and one of
    // the corresponding values.

    _.object = function (list, values) {
        var result = {};

        for (var i = 0, length = list && list.length; i < length; i++) {
            if (values) {
                result[list[i]] = values[i];
            } else {
                result[list[i][0]] = list[i][1];
            }
        }

        return result;
    }; // Return the position of the first occurrence of an item in an array,
    // or -1 if the item is not included in the array.
    // If the array is large and already in sort order, pass `true`
    // for **isSorted** to use binary search.

    _.indexOf = function (array, item, isSorted) {
        var i = 0,
            length = array && array.length;

        if (typeof isSorted == 'number') {
            i = isSorted < 0 ? Math.max(0, length + isSorted) : isSorted;
        } else if (isSorted && length) {
            i = _.sortedIndex(array, item);
            return array[i] === item ? i : -1;
        }

        if (item !== item) {
            return _.findIndex(slice.call(array, i), _.isNaN);
        }

        for (; i < length; i++) if (array[i] === item) return i;

        return -1;
    };

    _.lastIndexOf = function (array, item, from) {
        var idx = array ? array.length : 0;

        if (typeof from == 'number') {
            idx = from < 0 ? idx + from + 1 : Math.min(idx, from + 1);
        }

        if (item !== item) {
            return _.findLastIndex(slice.call(array, 0, idx), _.isNaN);
        }

        while (--idx >= 0) if (array[idx] === item) return idx;

        return -1;
    }; // Generator function to create the findIndex and findLastIndex functions

    function createIndexFinder(dir) {
        return function (array, predicate, context) {
            predicate = cb(predicate, context);
            var length = array != null && array.length;
            var index = dir > 0 ? 0 : length - 1;

            for (; index >= 0 && index < length; index += dir) {
                if (predicate(array[index], index, array)) return index;
            }

            return -1;
        };
    } // Returns the first index on an array-like that passes a predicate test

    _.findIndex = createIndexFinder(1);
    _.findLastIndex = createIndexFinder(-1); // Use a comparator function to figure out the smallest index at which
    // an object should be inserted so as to maintain order. Uses binary search.

    _.sortedIndex = function (array, obj, iteratee, context) {
        iteratee = cb(iteratee, context, 1);
        var value = iteratee(obj);
        var low = 0,
            high = array.length;

        while (low < high) {
            var mid = Math.floor((low + high) / 2);
            if (iteratee(array[mid]) < value) low = mid + 1;
            else high = mid;
        }

        return low;
    }; // Generate an integer Array containing an arithmetic progression. A port of
    // the native Python `range()` function. See
    // [the Python documentation](http://docs.python.org/library/functions.html#range).

    _.range = function (start, stop, step) {
        if (arguments.length <= 1) {
            stop = start || 0;
            start = 0;
        }

        step = step || 1;
        var length = Math.max(Math.ceil((stop - start) / step), 0);
        var range = Array(length);

        for (var idx = 0; idx < length; idx++, start += step) {
            range[idx] = start;
        }

        return range;
    }; // Function (ahem) Functions
    // ------------------
    // Determines whether to execute a function as a constructor
    // or a normal function with the provided arguments

    var executeBound = function (sourceFunc, boundFunc, context, callingContext, args) {
        if (!(callingContext instanceof boundFunc)) return sourceFunc.apply(context, args);
        var self = baseCreate(sourceFunc.prototype);
        var result = sourceFunc.apply(self, args);
        if (_.isObject(result)) return result;
        return self;
    }; // Create a function bound to a given object (assigning `this`, and arguments,
    // optionally). Delegates to **ECMAScript 5**'s native `Function.bind` if
    // available.

    _.bind = function (func, context) {
        if (nativeBind && func.bind === nativeBind) return nativeBind.apply(func, slice.call(arguments, 1));
        if (!_.isFunction(func)) throw new TypeError('Bind must be called on a function');
        var args = slice.call(arguments, 2);

        var bound = function () {
            return executeBound(func, bound, context, this, args.concat(slice.call(arguments)));
        };

        return bound;
    }; // Partially apply a function by creating a version that has had some of its
    // arguments pre-filled, without changing its dynamic `this` context. _ acts
    // as a placeholder, allowing any combination of arguments to be pre-filled.

    _.partial = function (func) {
        var boundArgs = slice.call(arguments, 1);

        var bound = function () {
            var position = 0,
                length = boundArgs.length;
            var args = Array(length);

            for (var i = 0; i < length; i++) {
                args[i] = boundArgs[i] === _ ? arguments[position++] : boundArgs[i];
            }

            while (position < arguments.length) args.push(arguments[position++]);

            return executeBound(func, bound, this, this, args);
        };

        return bound;
    }; // Bind a number of an object's methods to that object. Remaining arguments
    // are the method names to be bound. Useful for ensuring that all callbacks
    // defined on an object belong to it.

    _.bindAll = function (obj) {
        var i,
            length = arguments.length,
            key;
        if (length <= 1) throw new Error('bindAll must be passed function names');

        for (i = 1; i < length; i++) {
            key = arguments[i];
            obj[key] = _.bind(obj[key], obj);
        }

        return obj;
    }; // Memoize an expensive function by storing its results.

    _.memoize = function (func, hasher) {
        var memoize = function (key) {
            var cache = memoize.cache;
            var address = '' + (hasher ? hasher.apply(this, arguments) : key);
            if (!_.has(cache, address)) cache[address] = func.apply(this, arguments);
            return cache[address];
        };

        memoize.cache = {};
        return memoize;
    }; // Delays a function for the given number of milliseconds, and then calls
    // it with the arguments supplied.

    _.delay = function (func, wait) {
        var args = slice.call(arguments, 2);
        return setTimeout(function () {
            return func.apply(null, args);
        }, wait);
    }; // Defers a function, scheduling it to run after the current call stack has
    // cleared.

    _.defer = _.partial(_.delay, _, 1); // Returns a function, that, when invoked, will only be triggered at most once
    // during a given window of time. Normally, the throttled function will run
    // as much as it can, without ever going more than once per `wait` duration;
    // but if you'd like to disable the execution on the leading edge, pass
    // `{leading: false}`. To disable execution on the trailing edge, ditto.

    _.throttle = function (func, wait, options) {
        var context, args, result;
        var timeout = null;
        var previous = 0;
        if (!options) options = {};

        var later = function () {
            previous = options.leading === false ? 0 : _.now();
            timeout = null;
            result = func.apply(context, args);
            if (!timeout) context = args = null;
        };

        return function () {
            var now = _.now();

            if (!previous && options.leading === false) previous = now;
            var remaining = wait - (now - previous);
            context = this;
            args = arguments;

            if (remaining <= 0 || remaining > wait) {
                if (timeout) {
                    clearTimeout(timeout);
                    timeout = null;
                }

                previous = now;
                result = func.apply(context, args);
                if (!timeout) context = args = null;
            } else if (!timeout && options.trailing !== false) {
                timeout = setTimeout(later, remaining);
            }

            return result;
        };
    }; // Returns a function, that, as long as it continues to be invoked, will not
    // be triggered. The function will be called after it stops being called for
    // N milliseconds. If `immediate` is passed, trigger the function on the
    // leading edge, instead of the trailing.

    _.debounce = function (func, wait, immediate) {
        var timeout, args, context, timestamp, result;

        var later = function () {
            var last = _.now() - timestamp;

            if (last < wait && last >= 0) {
                timeout = setTimeout(later, wait - last);
            } else {
                timeout = null;

                if (!immediate) {
                    result = func.apply(context, args);
                    if (!timeout) context = args = null;
                }
            }
        };

        return function () {
            context = this;
            args = arguments;
            timestamp = _.now();
            var callNow = immediate && !timeout;
            if (!timeout) timeout = setTimeout(later, wait);

            if (callNow) {
                result = func.apply(context, args);
                context = args = null;
            }

            return result;
        };
    }; // Returns the first function passed as an argument to the second,
    // allowing you to adjust arguments, run code before and after, and
    // conditionally execute the original function.

    _.wrap = function (func, wrapper) {
        return _.partial(wrapper, func);
    }; // Returns a negated version of the passed-in predicate.

    _.negate = function (predicate) {
        return function () {
            return !predicate.apply(this, arguments);
        };
    }; // Returns a function that is the composition of a list of functions, each
    // consuming the return value of the function that follows.

    _.compose = function () {
        var args = arguments;
        var start = args.length - 1;
        return function () {
            var i = start;
            var result = args[start].apply(this, arguments);

            while (i--) result = args[i].call(this, result);

            return result;
        };
    }; // Returns a function that will only be executed on and after the Nth call.

    _.after = function (times, func) {
        return function () {
            if (--times < 1) {
                return func.apply(this, arguments);
            }
        };
    }; // Returns a function that will only be executed up to (but not including) the Nth call.

    _.before = function (times, func) {
        var memo;
        return function () {
            if (--times > 0) {
                memo = func.apply(this, arguments);
            }

            if (times <= 1) func = null;
            return memo;
        };
    }; // Returns a function that will be executed at most one time, no matter how
    // often you call it. Useful for lazy initialization.

    _.once = _.partial(_.before, 2); // Object Functions
    // ----------------
    // Keys in IE < 9 that won't be iterated by `for key in ...` and thus missed.

    var hasEnumBug = !{
        toString: null
    }.propertyIsEnumerable('toString');
    var nonEnumerableProps = ['valueOf', 'isPrototypeOf', 'toString', 'propertyIsEnumerable', 'hasOwnProperty', 'toLocaleString'];

    function collectNonEnumProps(obj, keys) {
        var nonEnumIdx = nonEnumerableProps.length;
        var constructor = obj.constructor;
        var proto = (_.isFunction(constructor) && constructor.prototype) || ObjProto; // Constructor is a special case.

        var prop = 'constructor';
        if (_.has(obj, prop) && !_.contains(keys, prop)) keys.push(prop);

        while (nonEnumIdx--) {
            prop = nonEnumerableProps[nonEnumIdx];

            if (prop in obj && obj[prop] !== proto[prop] && !_.contains(keys, prop)) {
                keys.push(prop);
            }
        }
    } // Retrieve the names of an object's own properties.
    // Delegates to **ECMAScript 5**'s native `Object.keys`

    _.keys = function (obj) {
        if (!_.isObject(obj)) return [];
        if (nativeKeys) return nativeKeys(obj);
        var keys = [];

        for (var key in obj) if (_.has(obj, key)) keys.push(key); // Ahem, IE < 9.

        if (hasEnumBug) collectNonEnumProps(obj, keys);
        return keys;
    }; // Retrieve all the property names of an object.

    _.allKeys = function (obj) {
        if (!_.isObject(obj)) return [];
        var keys = [];

        for (var key in obj) keys.push(key); // Ahem, IE < 9.

        if (hasEnumBug) collectNonEnumProps(obj, keys);
        return keys;
    }; // Retrieve the values of an object's properties.

    _.values = function (obj) {
        var keys = _.keys(obj);

        var length = keys.length;
        var values = Array(length);

        for (var i = 0; i < length; i++) {
            values[i] = obj[keys[i]];
        }

        return values;
    }; // Returns the results of applying the iteratee to each element of the object
    // In contrast to _.map it returns an object

    _.mapObject = function (obj, iteratee, context) {
        iteratee = cb(iteratee, context);

        var keys = _.keys(obj),
            length = keys.length,
            results = {},
            currentKey;

        for (var index = 0; index < length; index++) {
            currentKey = keys[index];
            results[currentKey] = iteratee(obj[currentKey], currentKey, obj);
        }

        return results;
    }; // Convert an object into a list of `[key, value]` pairs.

    _.pairs = function (obj) {
        var keys = _.keys(obj);

        var length = keys.length;
        var pairs = Array(length);

        for (var i = 0; i < length; i++) {
            pairs[i] = [keys[i], obj[keys[i]]];
        }

        return pairs;
    }; // Invert the keys and values of an object. The values must be serializable.

    _.invert = function (obj) {
        var result = {};

        var keys = _.keys(obj);

        for (var i = 0, length = keys.length; i < length; i++) {
            result[obj[keys[i]]] = keys[i];
        }

        return result;
    }; // Return a sorted list of the function names available on the object.
    // Aliased as `methods`

    _.functions = _.methods = function (obj) {
        var names = [];

        for (var key in obj) {
            if (_.isFunction(obj[key])) names.push(key);
        }

        return names.sort();
    }; // Extend a given object with all the properties in passed-in object(s).

    _.extend = createAssigner(_.allKeys); // Assigns a given object with all the own properties in the passed-in object(s)
    // (https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object/assign)

    _.extendOwn = _.assign = createAssigner(_.keys); // Returns the first key on an object that passes a predicate test

    _.findKey = function (obj, predicate, context) {
        predicate = cb(predicate, context);

        var keys = _.keys(obj),
            key;

        for (var i = 0, length = keys.length; i < length; i++) {
            key = keys[i];
            if (predicate(obj[key], key, obj)) return key;
        }
    }; // Return a copy of the object only containing the whitelisted properties.

    _.pick = function (object, oiteratee, context) {
        var result = {},
            obj = object,
            iteratee,
            keys;
        if (obj == null) return result;

        if (_.isFunction(oiteratee)) {
            keys = _.allKeys(obj);
            iteratee = optimizeCb(oiteratee, context);
        } else {
            keys = flatten(arguments, false, false, 1);

            iteratee = function (value, key, obj) {
                return key in obj;
            };

            obj = Object(obj);
        }

        for (var i = 0, length = keys.length; i < length; i++) {
            var key = keys[i];
            var value = obj[key];
            if (iteratee(value, key, obj)) result[key] = value;
        }

        return result;
    }; // Return a copy of the object without the blacklisted properties.

    _.omit = function (obj, iteratee, context) {
        if (_.isFunction(iteratee)) {
            iteratee = _.negate(iteratee);
        } else {
            var keys = _.map(flatten(arguments, false, false, 1), String);

            iteratee = function (value, key) {
                return !_.contains(keys, key);
            };
        }

        return _.pick(obj, iteratee, context);
    }; // Fill in a given object with default properties.

    _.defaults = createAssigner(_.allKeys, true); // Creates an object that inherits from the given prototype object.
    // If additional properties are provided then they will be added to the
    // created object.

    _.create = function (prototype, props) {
        var result = baseCreate(prototype);
        if (props) _.extendOwn(result, props);
        return result;
    }; // Create a (shallow-cloned) duplicate of an object.

    _.clone = function (obj) {
        if (!_.isObject(obj)) return obj;
        return _.isArray(obj) ? obj.slice() : _.extend({}, obj);
    }; // Invokes interceptor with the obj, and then returns obj.
    // The primary purpose of this method is to "tap into" a method chain, in
    // order to perform operations on intermediate results within the chain.

    _.tap = function (obj, interceptor) {
        interceptor(obj);
        return obj;
    }; // Returns whether an object has a given set of `key:value` pairs.

    _.isMatch = function (object, attrs) {
        var keys = _.keys(attrs),
            length = keys.length;

        if (object == null) return !length;
        var obj = Object(object);

        for (var i = 0; i < length; i++) {
            var key = keys[i];
            if (attrs[key] !== obj[key] || !(key in obj)) return false;
        }

        return true;
    }; // Internal recursive comparison function for `isEqual`.

    var eq = function (a, b, aStack, bStack) {
        // Identical objects are equal. `0 === -0`, but they aren't identical.
        // See the [Harmony `egal` proposal](http://wiki.ecmascript.org/doku.php?id=harmony:egal).
        if (a === b) return a !== 0 || 1 / a === 1 / b; // A strict comparison is necessary because `null == undefined`.

        if (a == null || b == null) return a === b; // Unwrap any wrapped objects.

        if (a instanceof _) a = a._wrapped;
        if (b instanceof _) b = b._wrapped; // Compare `[[Class]]` names.

        var className = toString.call(a);
        if (className !== toString.call(b)) return false;

        switch (className) {
            // Strings, numbers, regular expressions, dates, and booleans are compared by value.
            case '[object RegExp]': // RegExps are coerced to strings for comparison (Note: '' + /a/i === '/a/i')

            case '[object String]':
                // Primitives and their corresponding object wrappers are equivalent; thus, `"5"` is
                // equivalent to `new String("5")`.
                return '' + a === '' + b;

            case '[object Number]':
                // `NaN`s are equivalent, but non-reflexive.
                // Object(NaN) is equivalent to NaN
                if (+a !== +a) return +b !== +b; // An `egal` comparison is performed for other numeric values.

                return +a === 0 ? 1 / +a === 1 / b : +a === +b;

            case '[object Date]':
            case '[object Boolean]':
                // Coerce dates and booleans to numeric primitive values. Dates are compared by their
                // millisecond representations. Note that invalid dates with millisecond representations
                // of `NaN` are not equivalent.
                return +a === +b;
        }

        var areArrays = className === '[object Array]';

        if (!areArrays) {
            if (typeof a != 'object' || typeof b != 'object') return false; // Objects with different constructors are not equivalent, but `Object`s or `Array`s
            // from different frames are.

            var aCtor = a.constructor,
                bCtor = b.constructor;

            if (aCtor !== bCtor && !(_.isFunction(aCtor) && aCtor instanceof aCtor && _.isFunction(bCtor) && bCtor instanceof bCtor) && 'constructor' in a && 'constructor' in b) {
                return false;
            }
        } // Assume equality for cyclic structures. The algorithm for detecting cyclic
        // structures is adapted from ES 5.1 section 15.12.3, abstract operation `JO`.
        // Initializing stack of traversed objects.
        // It's done here since we only need them for objects and arrays comparison.

        aStack = aStack || [];
        bStack = bStack || [];
        var length = aStack.length;

        while (length--) {
            // Linear search. Performance is inversely proportional to the number of
            // unique nested structures.
            if (aStack[length] === a) return bStack[length] === b;
        } // Add the first object to the stack of traversed objects.

        aStack.push(a);
        bStack.push(b); // Recursively compare objects and arrays.

        if (areArrays) {
            // Compare array lengths to determine if a deep comparison is necessary.
            length = a.length;
            if (length !== b.length) return false; // Deep compare the contents, ignoring non-numeric properties.

            while (length--) {
                if (!eq(a[length], b[length], aStack, bStack)) return false;
            }
        } else {
            // Deep compare objects.
            var keys = _.keys(a),
                key;

            length = keys.length; // Ensure that both objects contain the same number of properties before comparing deep equality.

            if (_.keys(b).length !== length) return false;

            while (length--) {
                // Deep compare each member
                key = keys[length];
                if (!(_.has(b, key) && eq(a[key], b[key], aStack, bStack))) return false;
            }
        } // Remove the first object from the stack of traversed objects.

        aStack.pop();
        bStack.pop();
        return true;
    }; // Perform a deep comparison to check if two objects are equal.

    _.isEqual = function (a, b) {
        return eq(a, b);
    }; // Is a given array, string, or object empty?
    // An "empty" object has no enumerable own-properties.

    _.isEmpty = function (obj) {
        if (obj == null) return true;
        if (isArrayLike(obj) && (_.isArray(obj) || _.isString(obj) || _.isArguments(obj))) return obj.length === 0;
        return _.keys(obj).length === 0;
    }; // Is a given value a DOM element?

    _.isElement = function (obj) {
        return !!(obj && obj.nodeType === 1);
    }; // Is a given value an array?
    // Delegates to ECMA5's native Array.isArray

    _.isArray =
        nativeIsArray ||
        function (obj) {
            return toString.call(obj) === '[object Array]';
        }; // Is a given variable an object?

    _.isObject = function (obj) {
        var type = typeof obj;
        return type === 'function' || (type === 'object' && !!obj);
    }; // Add some isType methods: isArguments, isFunction, isString, isNumber, isDate, isRegExp, isError.

    _.each(['Arguments', 'Function', 'String', 'Number', 'Date', 'RegExp', 'Error'], function (name) {
        _['is' + name] = function (obj) {
            return toString.call(obj) === '[object ' + name + ']';
        };
    }); // Define a fallback version of the method in browsers (ahem, IE < 9), where
    // there isn't any inspectable "Arguments" type.

    if (!_.isArguments(arguments)) {
        _.isArguments = function (obj) {
            return _.has(obj, 'callee');
        };
    } // Optimize `isFunction` if appropriate. Work around some typeof bugs in old v8,
    // IE 11 (#1621), and in Safari 8 (#1929).

    if (typeof /./ != 'function' && typeof Int8Array != 'object') {
        _.isFunction = function (obj) {
            return typeof obj == 'function' || false;
        };
    } // Is a given object a finite number?

    _.isFinite = function (obj) {
        return isFinite(obj) && !isNaN(parseFloat(obj));
    }; // Is the given value `NaN`? (NaN is the only number which does not equal itself).

    _.isNaN = function (obj) {
        return _.isNumber(obj) && obj !== +obj;
    }; // Is a given value a boolean?

    _.isBoolean = function (obj) {
        return obj === true || obj === false || toString.call(obj) === '[object Boolean]';
    }; // Is a given value equal to null?

    _.isNull = function (obj) {
        return obj === null;
    }; // Is a given variable undefined?

    _.isUndefined = function (obj) {
        return obj === void 0;
    }; // Shortcut function for checking if an object has a given property directly
    // on itself (in other words, not on a prototype).

    _.has = function (obj, key) {
        return obj != null && hasOwnProperty.call(obj, key);
    }; // Utility Functions
    // -----------------
    // Run Underscore.js in *noConflict* mode, returning the `_` variable to its
    // previous owner. Returns a reference to the Underscore object.

    _.noConflict = function () {
        root._ = previousUnderscore;
        return this;
    }; // Keep the identity function around for default iteratees.

    _.identity = function (value) {
        return value;
    }; // Predicate-generating functions. Often useful outside of Underscore.

    _.constant = function (value) {
        return function () {
            return value;
        };
    };

    _.noop = function () {};

    _.property = function (key) {
        return function (obj) {
            return obj == null ? void 0 : obj[key];
        };
    }; // Generates a function for a given object that returns a given property.

    _.propertyOf = function (obj) {
        return obj == null
            ? function () {}
            : function (key) {
                  return obj[key];
              };
    }; // Returns a predicate for checking whether an object has a given set of
    // `key:value` pairs.

    _.matcher = _.matches = function (attrs) {
        attrs = _.extendOwn({}, attrs);
        return function (obj) {
            return _.isMatch(obj, attrs);
        };
    }; // Run a function **n** times.

    _.times = function (n, iteratee, context) {
        var accum = Array(Math.max(0, n));
        iteratee = optimizeCb(iteratee, context, 1);

        for (var i = 0; i < n; i++) accum[i] = iteratee(i);

        return accum;
    }; // Return a random integer between min and max (inclusive).

    _.random = function (min, max) {
        if (max == null) {
            max = min;
            min = 0;
        }

        return min + Math.floor(Math.random() * (max - min + 1));
    }; // A (possibly faster) way to get the current timestamp as an integer.

    _.now =
        Date.now ||
        function () {
            return new Date().getTime();
        }; // List of HTML entities for escaping.

    var escapeMap = {
        '&': '&amp;',
        '<': '&lt;',
        '>': '&gt;',
        '"': '&quot;',
        "'": '&#x27;',
        '`': '&#x60;'
    };

    var unescapeMap = _.invert(escapeMap); // Functions for escaping and unescaping strings to/from HTML interpolation.

    var createEscaper = function (map) {
        var escaper = function (match) {
            return map[match];
        }; // Regexes for identifying a key that needs to be escaped

        var source = '(?:' + _.keys(map).join('|') + ')';
        var testRegexp = RegExp(source);
        var replaceRegexp = RegExp(source, 'g');
        return function (string) {
            string = string == null ? '' : '' + string;
            return testRegexp.test(string) ? string.replace(replaceRegexp, escaper) : string;
        };
    };

    _.escape = createEscaper(escapeMap);
    _.unescape = createEscaper(unescapeMap); // If the value of the named `property` is a function then invoke it with the
    // `object` as context; otherwise, return it.

    _.result = function (object, property, fallback) {
        var value = object == null ? void 0 : object[property];

        if (value === void 0) {
            value = fallback;
        }

        return _.isFunction(value) ? value.call(object) : value;
    }; // Generate a unique integer id (unique within the entire client session).
    // Useful for temporary DOM ids.

    var idCounter = 0;

    _.uniqueId = function (prefix) {
        var id = ++idCounter + '';
        return prefix ? prefix + id : id;
    }; // By default, Underscore uses ERB-style template delimiters, change the
    // following template settings to use alternative delimiters.

    _.templateSettings = {
        evaluate: /<%([\s\S]+?)%>/g,
        interpolate: /<%=([\s\S]+?)%>/g,
        escape: /<%-([\s\S]+?)%>/g
    }; // When customizing `templateSettings`, if you don't want to define an
    // interpolation, evaluation or escaping regex, we need one that is
    // guaranteed not to match.

    var noMatch = /(.)^/; // Certain characters need to be escaped so that they can be put into a
    // string literal.

    var escapes = {
        "'": "'",
        '\\': '\\',
        '\r': 'r',
        '\n': 'n',
        '\u2028': 'u2028',
        '\u2029': 'u2029'
    };
    var escaper = /\\|'|\r|\n|\u2028|\u2029/g;

    var escapeChar = function (match) {
        return '\\' + escapes[match];
    }; // JavaScript micro-templating, similar to John Resig's implementation.
    // Underscore templating handles arbitrary delimiters, preserves whitespace,
    // and correctly escapes quotes within interpolated code.
    // NB: `oldSettings` only exists for backwards compatibility.

    _.template = function (text, settings, oldSettings) {
        if (!settings && oldSettings) settings = oldSettings;
        settings = _.defaults({}, settings, _.templateSettings); // Combine delimiters into one regular expression via alternation.

        var matcher = RegExp([(settings.escape || noMatch).source, (settings.interpolate || noMatch).source, (settings.evaluate || noMatch).source].join('|') + '|$', 'g'); // Compile the template source, escaping string literals appropriately.

        var index = 0;
        var source = "__p+='";
        text.replace(matcher, function (match, escape, interpolate, evaluate, offset) {
            source += text.slice(index, offset).replace(escaper, escapeChar);
            index = offset + match.length;

            if (escape) {
                source += "'+\n((__t=(" + escape + "))==null?'':_.escape(__t))+\n'";
            } else if (interpolate) {
                source += "'+\n((__t=(" + interpolate + "))==null?'':__t)+\n'";
            } else if (evaluate) {
                source += "';\n" + evaluate + "\n__p+='";
            } // Adobe VMs need the match returned to produce the correct offest.

            return match;
        });
        source += "';\n"; // If a variable is not specified, place data values in local scope.

        if (!settings.variable) source = 'with(obj||{}){\n' + source + '}\n';
        source = "var __t,__p='',__j=Array.prototype.join," + "print=function(){__p+=__j.call(arguments,'');};\n" + source + 'return __p;\n';

        try {
            var render = new Function(settings.variable || 'obj', '_', source);
        } catch (e) {
            e.source = source;
            throw e;
        }

        var template = function (data) {
            return render.call(this, data, _);
        }; // Provide the compiled source as a convenience for precompilation.

        var argument = settings.variable || 'obj';
        template.source = 'function(' + argument + '){\n' + source + '}';
        return template;
    }; // Add a "chain" function. Start chaining a wrapped Underscore object.

    _.chain = function (obj) {
        var instance = _(obj);

        instance._chain = true;
        return instance;
    }; // OOP
    // ---------------
    // If Underscore is called as a function, it returns a wrapped object that
    // can be used OO-style. This wrapper holds altered versions of all the
    // underscore functions. Wrapped objects may be chained.
    // Helper function to continue chaining intermediate results.

    var result = function (instance, obj) {
        return instance._chain ? _(obj).chain() : obj;
    }; // Add your own custom functions to the Underscore object.

    _.mixin = function (obj) {
        _.each(_.functions(obj), function (name) {
            var func = (_[name] = obj[name]);

            _.prototype[name] = function () {
                var args = [this._wrapped];
                push.apply(args, arguments);
                return result(this, func.apply(_, args));
            };
        });
    }; // Add all of the Underscore functions to the wrapper object.

    _.mixin(_); // Add all mutator Array functions to the wrapper.

    _.each(['pop', 'push', 'reverse', 'shift', 'sort', 'splice', 'unshift'], function (name) {
        var method = ArrayProto[name];

        _.prototype[name] = function () {
            var obj = this._wrapped;
            method.apply(obj, arguments);
            if ((name === 'shift' || name === 'splice') && obj.length === 0) delete obj[0];
            return result(this, obj);
        };
    }); // Add all accessor Array functions to the wrapper.

    _.each(['concat', 'join', 'slice'], function (name) {
        var method = ArrayProto[name];

        _.prototype[name] = function () {
            return result(this, method.apply(this._wrapped, arguments));
        };
    }); // Extracts the result from a wrapped and chained object.

    _.prototype.value = function () {
        return this._wrapped;
    }; // Provide unwrapping proxy for some methods used in engine operations
    // such as arithmetic and JSON stringification.

    _.prototype.valueOf = _.prototype.toJSON = _.prototype.value;

    _.prototype.toString = function () {
        return '' + this._wrapped;
    }; // AMD registration happens at the end for compatibility with AMD loaders
    // that may not enforce next-turn semantics on modules. Even though general
    // practice for AMD registration is to be anonymous, underscore registers
    // as a named module because, like jQuery, it is a base library that is
    // popular enough to be bundled in a third party lib, but not be part of
    // an AMD load request. Those cases could generate an error when an
    // anonymous define() is called outside of a loader request.
    //   if (typeof define === 'function' && define.amd) {
    //     define('underscore', [], function() {
    //       return _;
    //     });
    //   }
}.call(this));
